Diarrheagenic pathogens in Polymicrobial infections

During systematic active surveillance of the causes of diarrhea in patients admitted to the Infectious Diseases and Beliaghata General Hospital in Kolkata, India, we looked for 26 known gastrointestinal pathogens in fecal samples from 2,748 patients. Samples from about one-third (29%) of the patients contained multiple pathogens. Polymicrobial infections frequently contained Vibrio cholerae O1 and rotavirus. When these agents were present, some coinfecting agents were found signifi cantly less often (p = 10^-5 to 10^-33), some were detected signifi cantly more often (p = 10^-5 to 10-26), and others were detected equally as often as when V. cholerae O1 or rotavirus was absent. When data were stratifi ed by patient age and season, many nonrandom associations remained statistically signifi cant. The causes and effects of these nonrandom associations remain unknown.